pfSense - pfSense is a free and open source firewall and router that also features unified threat management, load balancing, multi WAN, and more
IPFire - IPFire is a server distribution with intended to use as a firewall.
Zentyal - Linux directory, domain, mail, gateway and infrastructure server for SMBs.
OPNsense - OPNsense® you next open source firewall. Free Download. High-end Security Made Easy™. Offers Intrusion Prevention, Captive Portal, Traffic Shaping and more.
NethServer - NethServer is an operating system for Linux enthusiasts, designed for small offices and medium...
Endian Firewall Community - Endian Firewall Community (EFW) is a "turn-key" linux security distribution that turns...